﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;

namespace Chizx.Common
{
    public class IPHelper
    {
        /**/
        /// <summary> 
        /// 取得客户端真实IP。如果有代理则取第一个非内网地址 
        /// </summary> 
        public static string getIPAddress()
        {
            string result = String.Empty;
            result = System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
            if (result != null && result != String.Empty)
            {
                //可能有代理 
                if (result.IndexOf(".") == -1)     //没有“.”肯定是非IPv4格式 
                    result = null;
                else
                {
                    if (result.IndexOf(",") != -1)
                    {
                        //有“,”，估计多个代理。取第一个不是内网的IP。 
                        result = result.Replace(" ", "").Replace("'", "");
                        string[] temparyip = result.Split(",;".ToCharArray());
                        for (int i = 0; i < temparyip.Length; i++)
                        {
                            if (IsIPAddress(temparyip[i])
                                && temparyip[i].Substring(0, 3) != "10."
                                && temparyip[i].Substring(0, 7) != "192.168"
                                && temparyip[i].Substring(0, 7) != "172.16.")
                            {
                                return temparyip[i];     //找到不是内网的地址 
                            }
                        }
                    }
                    else if (IsIPAddress(result)) //代理即是IP格式 
                        return result;
                    else
                        result = null;     //代理中的内容 非IP，取IP 
                }
            }
            string IpAddress = (System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null && System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != String.Empty) ? System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] : System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
            if (null == result || result == String.Empty)
                result = System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
            if (result == null || result == String.Empty)
                result = System.Web.HttpContext.Current.Request.UserHostAddress;
            return result;
        }


        /// <summary>
        /// 获取客户端ip地址:不识别代理
        /// </summary>
        /// <returns></returns>
        public string GetClientIP()
        {
            string result = System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
            if (null == result || result == String.Empty)
            {
                result = System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
            }

            if (null == result || result == String.Empty)
            {
                result = System.Web.HttpContext.Current.Request.UserHostAddress;
            }
            return result;
        }


        #region bool IsIPAddress(str1) 判断是否是IP格式
        /**/
        /// <summary>
        /// 判断是否是IP地址格式 0.0.0.0
        /// </summary>
        /// <param name="str1">待判断的IP地址</param>
        /// <returns>true or false</returns>
        public static bool IsIPAddress(string str1)
        {
            if (str1 == null || str1 == string.Empty || str1.Length < 7 || str1.Length > 15) return false;

            string regformat = @"^\d{1,3}[\.]\d{1,3}[\.]\d{1,3}[\.]\d{1,3}$";

            Regex regex = new Regex(regformat, RegexOptions.IgnoreCase);
            return regex.IsMatch(str1);
        }
        #endregion
    }
}
